期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1980
卷号:77
期号:3
页码:1270-1273
DOI:10.1073/pnas.77.3.1270
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Wild-type Brevibacterium flavum has been shown to possess arogenate dehydrogenase activity and to lack prephenate dehydrogenase, thereby providing presumptive evidence that arogenate (previously named "pretyrosine") is an obligatory intermediate of L-tyrosine biosynthesis. A similar enzymological pattern has been discerned in extracts made from wild-type cultures of various species of cyanobacteria. Application of rigorous molecular genetic criteria in confirmation of the exclusive role of arogenate in L-tyrosine synthesis was made possible by the isolation of an auxotrophic mutant exhibiting a nutritional requirement for L-tyrosine. The mutant was found to lack activity for arogenate dehydrogenase and to accumulate substantial amounts of arogenate behind the mutant block during starvation for L-tyrosine.